360 degree rotatable lifter arm for log singulator

ABSTRACT

The present invention  10  discloses a device for singulating individual logs from groups of logs for linear or transverse processing. The present invention discloses a log singulator having a fully rotatable lifter arm member, i.e., 360 degrees rotatable, which is used to singulate logs from groups of logs. The rotatable axle of the lifter arm may be located above the upstream “V” of the log cradle member. Furthermore, the lifter arm of the present invention will positively push the logs over the top point of the log cradle because it is rounded at the top point, thereby allowing the tip of lifter arm to remain in contact with the log. Lifter arms with 1 to 4 lifter arm tips are disclosed.

BACKGROUND OF THE INVENTION

[0001] This application claims benefit of Provisional Application SerialNo. 60/217,845 filed on Jul. 13, 2000.

FIELD OF THE INVENTION

[0002] The present invention relates generally to log singulators, andmore particularly, is concerned with a log singulator having a360-degree rotatable lifting arm.

DESCRIPTION OF THE PRIOR ART

[0003] Log singulators have been described in the prior art. However,none of the prior art devices disclose the unique features of thepresent invention.

[0004] In U.S. Pat. No. 5,423,47, dated Jun. 13, 1995, Redekop discloseda log singulator for sorting, feeding and indexing in a downstreamdirection a stack of logs into a stream of logs which has a firstnotched step and a first set of collectively actuable lift armspivotable about a first axis, and a second set of collectively actuablelift arms downstream of the first set of lift arms, actuableindependently of the first set of collectively actuable lift arms andpivotable about a second axis, the first set of lift arms actuable froma lowered position to a raised position whereby the first set of liftarms are engageable with a log at a first engagement point thereby toraise the log from the stack of logs, the first axis downstream of thefirst engagement point relative to the direction of movement of saidlogs in said stream of logs, the first axis generally below the firstnotched step, the first notched step adapted to receive and hold thestack of logs, the first set of lift arms in the raised positionpositioning the log so as to deposit the log into a second notched stepbelow the first set of lift arms in the raised position and downstreamof the first notched step, the second set of lift arms actuable from alowered position to a raised position whereby the second set of liftarms are engageable with the log in the second notched step at a secondengagement point thereby to raise the log from the second notched step,the second axis downstream of the second engagement point and generallybelow the second notched step, the second set of lift arms in the raisedposition positioning the log so as to deposit the log from the logsingulator.

[0005] In U.S. Pat. No. 5,174,351, dated Dec. 29, 1992, Lindenblatt, etal., disclosed an ending apparatus for positioning elongate objectscomprising, in combination, object singulating equipment for separatinga plurality of elongate objects in an inlet area into single objectswhile moving the objects in a first direction to an outlet area, andobject support rollers intermediate the inlet and outlet area forsupporting a separated, single elongate object. The object supportrollers are adapted to move the elongate object in a second directiontoward a reference surface independently of the object's movement in thefirst direction on the singulating device. The reference surface stopsmovement of the elongate object to establish a predetermined positionfor the elongate object. Establishing the position of the object permitsmore efficient handling during further processing.

[0006] In U.S. Pat. No. 4,585,114, dated Apr. 29, 1986, Lilianodisclosed an apparatus for the transfer of mandrels from a lube conveyerto a parallel mandrel pre-insertion line which comprises a plurality oftransfer devices each of which has an arm for the direct transfer of themandrels which is disappearingly movable transversely between the saidconveyor and the said line, and a further pair of arms, one fixed andone movable, having upper saw-tooth profiles cooperating to effect astepwise displacement of the mandrels between the conveyor and the saidline.

[0007] While these log singulators may be suitable for the purposes forwhich they were designed, they would not be as suitable for the purposesof the present invention, as hereinafter described.

SUMMARY OF THE INVENTION

[0008] The present invention discloses a device for singulatingindividual logs from groups of logs for linear or transverse processing.The present invention discloses a log singulator having a fullyrotatable lifter arm member, i.e., 360 degrees rotatable, which is usedto singulate logs from groups of logs. The rotatable axle of the lifterarm may be located above the upstream “V” of the log cradle member.Furthermore, the lifter arm of the present invention will positivelypush the logs over the top point of the log cradle because it is roundedat the top point, thereby allowing the tip of lifter arm to remain incontact with the log. Lifter arms with 1 to 4 lifter arm tips aredisclosed.

[0009] In log utilization facilities, the need exists to singulateindividual logs from groups of logs for linear or transverse processing.Several types of devices have been developed to accomplish this task.The devices currently available utilize a method of lifting logs overfixed generally V-shaped log cradles via a reciprocating motiongenerated by mechanical components. This particular motion has severaldisadvantages: the return motion of the lifting mechanism utilizes timein which the forward flow of logs being singulated is stopped; thereciprocating motion requires a bulky, complicated mechanism to performthe forward and backward motion; as logs are lifted over the top of theV-shaped log cradle, movement of the log to complete the motion to thebottom of the upstream V-shaped pocket is dependent on gravity; logswith knots or that are crooked may not slide into proper position; thereciprocating lifting device is of an eccentric design, meaning that itsweight is not balanced, and, this off center weight disadvantageutilizes approximately 25% of the total power to move a log from stageto stage; the V-shaped log cradles surfaces may be covered with smoothsteel plating, and, the plating makes crooked or knotty logs “stand off”from the bottom of the V log cradle, and, if the logs are too far awayfrom the lift position of the pocket, they will not be transferred fromstage to stage.

[0010] Objects and advantages of the present invention are to disclose asingulation device which does not reciprocate, but makes a full360-degree motion. The rotary motion device of the present invention hasseveral advantages. Since the rotary singulation motion is continuous,in a constant direction, there is no lost time waiting or the liftingdevice to return to start position and, therefore, productivity of therotary device is greatly improved over the reciprocating device. Thedrive unit for the rotary motion is direct connected to the liftmechanism, eliminating the need for a complicated mechanical means,e.g., a transmission, to develop the reciprocating motion. Because themotion is continuous, the shape of the rotating lift arm is designed sothat the log is positively guided into the bottom of the upstreamV-shaped log cradle which eliminates the possibility of knots or crookedlogs hanging on the pocket surfaces. The rotary lifting device is of aconcentric design, meaning that its weight is substantially totallybalanced. Due to it being balanced, a power savings of up to 25% perstage can be realized to lift the same size log as a reciprocatingdesign. In the rotary design, an open skid concept is utilized, meaningthat the V-shaped log cradles are not covered with steel plating.However, alternatively, the skids may be plated over. The open designallows crooked or knotty logs to lay in the open V-shaped log cradle,conforming to the shape of the log. This permits the log to be liftedinto the proper position so that logs can be more efficientlytransferred from stage to stage of the log singulator.

[0011] The foregoing and other objects and advantages will appear fromthe description to follow. In the description reference is made to theaccompanying drawings, which form a part hereof, and in which is shownby way of illustration specific embodiments in which the invention maybe practiced. These embodiments will be described in sufficient detailto enable those skilled in the art to practice the invention, and it isto be understood that other embodiments may be utilized and thatstructural changes may be made without departing from the scope of theinvention. In the accompanying drawings, like reference charactersdesignate the same or similar parts throughout the several views.

BRIEF DESCRIPTION OF THE DRAWINGS

[0012] In order that the invention may be more fully understood, it willnow be described, by way of example, with reference to the accompanyingdrawings in which:

[0013]FIG. 1 is a perspective view of the present invention.

[0014]FIG. 2 is a side elevation view of parts of the present invention.

[0015]FIG. 3 is a side elevation view of parts of the present invention.

[0016]FIG. 4 is a side elevation view of parts of the present invention.

[0017]FIG. 5 is a side elevation view of parts of the present invention.

[0018]FIG. 6 is a side elevation view of parts of the present invention.

[0019]FIG. 7 is a side elevation view of parts of the present invention.

LIST OF REFERENCE NUMERALS

[0020] With regard to reference numerals used, the following numberingis used throughout the drawings.

[0021]10 log singulator

[0022]12 lifter arm

[0023]14 axle

[0024]16 center line of axle

[0025]18 bottom

[0026]20 log cradle

[0027]22 log

[0028]24 top point

[0029]26 tip of lifter arm

[0030]28 sidewall

[0031]30 support members

[0032]32 front cross member

[0033]34 rear cross member

[0034]36 log cradle

[0035]38 log cradle

[0036]40 log cradle

[0037]42 log cradle

[0038]44 lifter arm

[0039]46 lifter arm

[0040]48 lifter arm

[0041]50 lifter arm face

DESCRIPTION OF THE PREFERRED EMBODIMENT(S)

[0042] Turning now descriptively to the drawings, in which similarreference characters denote similar elements throughout the severalviews, FIGS. 1 through 7 illustrate the present invention wherein a 360degree rotatable lifter arm for use on a log singulator is disclosed.

[0043] Turning to FIG. 1, therein is shown a perspective view of a logsingulator 10 having multiple lifter arms 12 installed thereon. Multipleaxles are provided 14 upon which the lifter arms 12 rotate which axleextends through and serves multiple lifter arms 12. The log singulatorcomprises a pair of sidewalls 28 and a plurality of vertically standingsupport members 30 held upright by a cross member 32 on the first,front, lower end of the log singulator 10 and a second, back, crossmember 34 on the rear or upper end of the log singulator 10. Axles 14are journalled through sidewalls 28 and support members 30 and equippedwith bearing means as would be done by one skilled in the art.Furthermore, means for rotating the multiple axles 14 in acounterclockwise and/or clockwise direction would also be provided. Itshould be seen that the log singulator 10 operates by moving logs in astepwise fashion up the log singulator by first moving a log from logcradle 36 to the next higher log cradle 38 and then up to the nexthigher log cradle 40 and then up onto the highest log singulator station42 where the log would then be moved by other machinery for furtherproceeding. The first set of lifter arms 44 move the log from log cradle36 downstream to log cradle 38 where a second set of lifter arms 46contact the logs to move them downstream to log cradle 40 where a thirdset of lifter arms 48 move the logs downstream to log cradle station 42.

[0044] Turning to FIG. 2, therein is shown a side view of the presentinvention 10 showing a left sidewall 28 along with a first lifter arm44, a second lifter arm 46, and a third lifter arm 48, all shown inrelationship to logs 22. It can be seen here that the lifter arms 12rotate 360 degrees. It should also be noted that as shown with lifterarm 46 that the tip of the lifter arm 26 is slightly longer than the toppoint 24 of the log cradle so that the lifter arm 46 will positivelypush the log 22 over the top point 24 of the log cradle because the logcradle is rounded at the top point 24, thereby allowing the tip 26 ofarm 46 to remain in contact with logs 22 in order to positively push thelogs 22 to the next higher or downstream log cradle. Front cross member32 is also shown.

[0045] Turning to FIG. 3, therein is shown a side elevation view ofanother lifter arm embodiment of the present invention 10. Shown thereinis the lifter arms 12 having a different design wherein the lifter armtips 26 overlap each other requiring that the lifter arms be disposedoff-center from each other in order to move logs downstream or up thelog singulator in order to allow tips 26 to clear each other.

[0046] Turning to FIG. 4, therein is shown a side elevation view ofanother lifter arm embodiment of the invention shown in FIG. 3 whereinthe lifter arms 12 are shown spaced apart so that the tips 26 thereof donot overlap; therefore, allowing the tips 26 of the lifter arms 12 toclear each other without being disposed off-center from each other.

[0047] Turning to FIG. 5, therein is shown a side elevation view ofanother lifter arm embodiment of the present invention wherein thelifter arms 12 have only one tip 26 having only one face with which tocontact logs 52.

[0048] Turning to FIG. 6, therein is shown a side elevation view ofanother lifter arm embodiment of the present invention wherein thelifter arms 12 have three tips 26 having three faces 50 with which tocontact logs 22.

[0049] Turning to FIG. 7, therein is shown a side elevation view ofanother lifter arm embodiment of the present invention wherein thelifter arms 12 have four tips 26 having four faces 50 with which tocontact logs 22.

[0050] Many specific details contained in the above description merelyillustrate some preferred embodiments and should not be construed as alimitation on the scope of the invention. Many other variations arepossible.

[0051] What is claimed to be new and desired to be protected by letterspatent is set forth in the appended claims:

I claim:
 1. A log singulator, wherein logs are moved from a front end toa back end of the log singulator, comprising: a) a first and a secondcross-member, said first cross-member being disposed on the front end ofthe log singulator, said front end being lower, said second cross-memberbeing disposed on the back end of the log singulator, said back endbeing higher, each of said first and second cross-members having a firstend and a second end; b) a pair of sidewalls connected between each ofsaid first and second ends of said first and said second cross-members,said sidewalls having journals therein for receiving an axle; c) aplurality of vertically standing support members disposed between saidpair of sidewalls, said support members connected between said first andsecond cross-members, said support members having journals therein forreceiving an axle; d) a plurality of axles, said axles being generallyhorizontal, said axles spaced apart between said first and said secondcross-members, said axles disposed in said journals of said pair ofsidewalls and said support members; e) a plurality of lifter armsdisposed on said axles; and, f) means for rotating said axles wherebythe axles and lifter arms rotate so that logs are moved from the frontend to the back end of the log singulator.
 2. The apparatus of claim 2,wherein said lifter arms rotate 360 degrees.